It becomes clear to be able to control propagation characteristics of an electromagnetic wave by periodically arranging conductor patterns having specific structure (hereinafter, referred to as metamaterial). As the most basic structural element in the metamaterial, a split-ring resonator which employs a C-shaped split-ring which is made by cutting a part of a ring-shaped conductor in the circumferential direction thereof is known. The split-ring resonator can control effective permeability by interacting with a magnetic field.
As an antenna with the split-ring resonator, a technology of Patent Literature 1 is disclosed.